BRP is often accepted, in lieu of driving license for bank account opening. https://www.lloydsbank.com/legal/proof-of-identity.html
I wouldn't call it a "not valid form of ID," when you can use them to board domestic flights, prove your age at establishments, and practically use it as an ID where they'd otherwise accept a driving license for ID.
PS: I hold one too.
They even state that: “The Biometric Residence Permit card may not be accepted in all our online journeys. You may need to provide additional documentation.”
Both HSBC and Barclays don’t accept them, not even to pick up a card from a branch.
EU identity cards are accepted but UK BRP and BRCs aren’t https://noidnosale.com/acceptable-forms-of-id-in-the-uk
If you managed to use yours for anything other than border control then it’s because whoever inspected it didn’t knew the rules.
Anytime I've had to verify identity online for bank account opening, it entailed taking a photo of my ID which then goes through automated ID checks via Jumio or similar APIs.
it's up to the service/goods provider what documents they accept which vary in terms of risk tolerance
"The biometric residence permit is proof of the holder’s right to stay, work or study in the UK. It can also be used as a form of identification (for example, if they wish to open a bank account in the UK). https://assets.publishing.service.gov.uk/government/uploads/...
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